Neutrinos from Starburst-Galaxies – A source stacking analysis of AMANDA II and IceCube data J. Dreyer1,2, J. K. Becker1, W. Rhode2, and the IceCube Collaboration3 1Theoretische Physik IV, Fakultät für Physik und Astronomie, Ruhr-Universität Bochum, 44780 Bochum, Germany 2Experimentelle Physik Vb, Fakultät Physik, TU Dortmund, 44221 Dortmund, Germany 3http://icecube.wisc.edu/
Received: 30 Oct 2010 – Accepted: 29 Nov 2010 – Published: 14 Jan 2011
Abstract. A stacking analysis performed with data from the IceCube neutrino observatory
is presented in this paper. In general, the stacking technique is
sensitive to a cumulative signal from a generic source class. This can
lead to a significant signal for the most luminous sources of the
class, even if the individual sources cannot be detected. Here, the
final data set of the AMANDA-II experiment, which is the predecessor of the IceCube, is used for an analysis.
In a second analysis,
data from a quarter of the IceCube detector is used. IceCube consists of so called stings, these are steel
cables with photo multipliers
hooked up which are deployed into the Antarctic ice to depths between 1450 m and 2450 m.
This analysis covers data taken with 22 strings of IceCube (IC-22) within one year.
For the first time, a sample of Starburst Galaxies was analyzed. In addition, several AGN catalogs are used as
well as a catalog of pulsars.
The analysis did not reveal a significant neutrino signal for any of
the analyzed source classes, neutrino flux limits were improved. The
strongest limit was received for the class of Gigahertz Peaked / Compact Steep Spectrum sources (GPS/CSS),
Eν2dNν/dEν|GPS< 8.2⋅10−12 GeV/s/sr per source, assuming an
Eν−2-shaped spectrum. This corresponds to an improvement
of a factor of 2.5 compared with the average point source limit for
single sources.
Citation: Dreyer, J., Becker, J. K., Rhode, W., and the IceCube Collaboration: Neutrinos from Starburst-Galaxies – A source stacking analysis of AMANDA II and IceCube data, Astrophys. Space Sci. Trans., 7, 7-10, doi:10.5194/astra-7-7-2011, 2011.